A model for target protein binding to calcium-activated S100 dimers.
S100 proteins are a family of dimeric calcium-binding proteins implicated in several cancers and neurological diseases. Calbindin D9k is an unusual monomeric member of the S100 family. A calbindin D9k mutant containing a novel calcium-induced helix is characterized. Based on sequence comparison, this helix could be a component of other S100 proteins and a factor in target protein binding. The origin of structural differences between three reported apo S100 dimer structures is verified. We conclude that the differences are a result of modeling rather than a function of different target binding properties. A mechanism for target protein binding is suggested.
Groves
P
P
Department of Molecular and Cellular Neurobiology, Nencki Institute of Experimental Biology, Warsaw, Poland. patrick@ameba.nencki.gov.pl
Finn
B E
BE
Kuźnicki
J
J
Forsén
S
S
D000818:Animals; D064026:Calbindins; D002118:Calcium / Q000378:metabolism*; D002135:Calcium-Binding Proteins / Q000737:chemistry / Q000378:metabolism; D002417:Cattle; D018797:Cell Cycle Proteins; D019281:Dimerization; D008958:Models, Molecular; D009154:Mutation; D009414:Nerve Growth Factors / Q000737:chemistry / Q000378:metabolism; D011485:Protein Binding; D011487:Protein Conformation; D051381:Rats; D000075383:S100 Calcium Binding Protein A6; D064030:S100 Calcium Binding Protein G / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D064568:S100 Calcium Binding Protein beta Subunit; D009418:S100 Proteins / Q000737:chemistry* / Q000378:metabolism
D064026:Calbindins; D002135:Calcium-Binding Proteins; D018797:Cell Cycle Proteins; D009414:Nerve Growth Factors; D000075383:S100 Calcium Binding Protein A6; D064030:S100 Calcium Binding Protein G; D064568:S100 Calcium Binding Protein beta Subunit; D009418:S100 Proteins; C489132:S100a6 protein, rat; C576508:S100g protein, rat; D002118:Calcium